Brumbies will target Lions' backline, which looks vulnerable after a series of injury problems

The Lions' hopes of victory in their last tour match before facing Australia will be tested by a hastily assembled backline and an ACT Brumbies side keen to inflict a timely psychological blow in Canberra on Tuesday.

Like all the provincial sides thrown to the Lions, the Brumbies will front up with a starting 15 robbed of their best Wallabies players but under strict orders to leave the tourists bruised, if not beaten, after full-time at Canberra Stadium.

The Lions notched up their fifth win from five tour matches against the New South Wales Waratahs on Saturday, running out 47-17 winners at Sydney Football Stadium, but the emphatic victory extracted a toll.

Centre Jamie Roberts was left nursing a suspected hamstring strain and could join England centre Manu Tuilagi in the treatment room, leaving the Lions vulnerable in the one area they can least afford it.

With Welshman George North also nursing hamstring concerns and fellow winger Tommy Bowe injured with a broken hand, Lions coach Warren Gatland has padded out his backline with a clutch of fly-ins led by 36-year-old Shane Williams.

The former Wales winger, who toured with the Lions in 2005 and 2009 and retired from international rugby at the end of 2011, flies in from Japan and will slot in for just the one match before leaving the squad to do media work.

Englishman Christian Wade, shipped in from Argentina, starts on the other wing, with Brad Barritt landing from the United States and starting at centre in the side captained by Ireland hooker Rory Best.

The cobbled-together backline, albeit complemented by a still-formidable forward pack, offers the Canberra-based Brumbies arguably the best chance of the Australian provincial sides to beat the Lions -- or at least leave the squad with a few doubts before the first Wallabies test on Saturday.

"We realise it's going to be tough on a few players, but there's some combinations with experience we looked at," Gatland told reporters in Sydney on Sunday.

"Having worked with him for a long time, I think he'll fit in pretty well with our game plan and will understand what we're trying to do, so there's some combinations and players who been there, done that before and knowing what's expected of them."

Gatland has also offered all of the players, barring Williams, the additional motivation of a spot in the team to play the Wallabies at Lang Park, despite his earlier intention to have the test side settled by the time of the Waratahs match.

"They have to have that belief that they can go out and perform on Tuesday and put your hand up and get selected for Saturday," Gatland said.

"There's no way we're going out sacrificing the game, I'm sure those players who go out on Tuesday night will be incredibly motivated to continue this tour unbeaten.

"And there's still that opportunity for players to put their hand up and say: 'I want to be part of that test team, that test 23' - and that's what their motivation has to be."

The Jake White-coached Brumbies have no intention of being cannon fodder and need only watch footage of their 2001 effort against the Lions for inspiration.

The Brumbies were gallant 30-28 losers at the same stadium in the previous tour in 2001 after utility back Austin Healey saved the Lions' blushes with a late try.

"This is a huge occasion for us as a team, but also individually," said White, who coached South Africa to their 2007 World Cup triumph.

"The Lions are one of rugby's last romantic sides, there is plenty of history there and we know that beating the Lions will go down in Canberra's rugby folklore for many years to come."

White, touted as a possible successor to Australia coach Robbie Deans, has guided the Brumbies to their first play-offs appearance in Super Rugby for nearly a decade this season and has a clutch of classy backs at his disposal, including live-wire fullback Jesse Mogg and winger Henry Speight.

Captain Peter Kimlin, who starts at number eight, and prop Scott Sio were also released from Wallabies duty for the match after earlier tour matches sparked criticism for offering the Lions uncompetitive teams.